Decline in ventricular function and clinical condition after Mustard repair for transposition of the great arteries (a prospective study of 22-29 years)

Great concern exists about the ability of the anatomic right ventricle to sustain the systemic circulation in patients with transposition of the great arteries who have undergone a Mustard procedure. A prospective study was made to examine long-term survival, clinical outcome, and right ventricular function 25 years after surgery. Ninety-one consecutive patients underwent the Mustard procedure between 1973 and 1980. After 14 years and again after 25 years (range 22-29 years), patients were studied with ECG, echocardiography, exercise testing, and Holter monitoring. The cumulative survival and event-free survival were 77% and 36%, respectively, after 25 years. Reoperation was necessary in 46%. No major loss of sinus rhythm was found. While all patients had good right ventricular function 14 years after repair, 61% of patients showed moderate-to-severe dysfunction after 25 years, when studied by echocardiography. Furthermore, the QRS complex widened and exercise capacity decreased. The anatomic right ventricle appears to be unable to sustain the systemic circulation at long-term follow-up and the clinical condition of patients late after Mustard repair is declining. We can expect more deaths or need for heart transplantation in the next decad